What is the recommended replacement of the j s option?

[zengh-cropty]

We were using the js together with a --preload to run geth in a private network using docker.
The main use-case was to mine blocks only when a transaction exists
(Similar to this https://ethereum.stackexchange.com/questions/3151/how-to-make-miner-to-mine-only-when-there-are-pending-transactions and this https://github.com/niksmac/ethereum-scripts/blob/master/src/mining-only-new-txs.js)
But now that the js is deprecated how can we achieve the same?
The only option we found so far, was to run console and use --preload.
Unfortunately, this requires us to also allow tty+std_open in docker which we would like to avoid.
Is there any way to do this?

[fjl]

Sorry, but the console and --preload option is the only way to achieve this now.

[holiman]

this requires us to also allow tty+std_open in docker which we would like to avoid.

Why does it require you to do that? That sounds like a bug to me. What happens if you don't ?

[s1na]

ACtually the flag we have for it is --exec console. It will execute the script and return without needing tty. However you have to write the script without callbacks. It --exec will not wait for callbacks to finish.